//第三题
import java.util.Scanner;
public class M80503 {
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        System.out.println("请输入磅数：");
        double bang=in.nextDouble();
        double ke=bang*0.4535924;
        System.out.println(ke+"千克");
    }
}
